Device for adjusting the length of a ski safety attachment

ABSTRACT

This invention concerns a basic arrangement of a ski binding having a front part or a toe end and a rear part or a heel end for securing the ski boot, and also having a front supporting part, longitudinally displaceable on a first base part fixed on the ski, for supporting the front boot holding part, and a rear supporting part, longitudinally displaceable on another base part fixed on the ski, for supporting the rear boot holding part. The invention further includes an adjusting device designed as a rack-and-pinion gear for simultaneous adjustment of both supporting parts; this adjusting device has two toothed racks, each connected to a supporting part, and a manually operable, lockable gearwheel which meshes with both toothed racks between the two supporting parts. In one embodiment, the gearwheel is arranged on a middle base part in an essentially stationary mount on the ski, and is separate from the front and rear base parts, and is held indirectly on the ski by the front and rear base parts. In another embodiment, the gearwheel has an unlocked position which is raised vertically relative to the top side of the ski for the rotational adjustment, and a locked position which is depressed toward the top side of the ski.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention concerns a basic arrangement of a ski binding having afront part or a toe end and a rear part or a heel end for securing theski boot, with

a front supporting part, longitudinally displaceable on a first basepart fixed on the ski, for the front boot holding part and a rearsupporting part, longitudinally displaceable on another base part fixedon the ski, for the rear boot holding part, and with

an adjusting device designed as a rack-and-pinion gear for simultaneousadjustment of both supporting parts, having two toothed racks, eachconnected to a supporting part, and a manually operable, lockablegearwheel which meshes with both toothed racks between the twosupporting parts.

2. Description of the Prior Art

Such a basic arrangement is the object of Austrian Patent 2630/90.According to this publication, the toothed racks in the area of thegearwheel pass through a housing which is designed on the one hand as abearing housing for the gearwheel and on the other hand as a toothedrack guide and holds the toothed racks constantly in a plane falling inthe radial mid-plane of a gearwheel. This housing is movable in thedirection of the vertical axis of the ski, i.e, the vertical position ofthis housing is defined by the toothed racks, and with flexing movementsof the ski, the vertical spacing of the housing changes relative to thetop side of the ski. A similar device is found in the German Patent DE41 35 899. Again, the device, which is in the middle of the ski, risesfrom the ski when the ski is bent.

By contrast, in Salomon, U.S. Pat. No. 3,987,553, a ski bindingadjustment device having a gear in a box which is screwed to the ski ispresented. Since the box is fixedly attached to the ski, this device hasno free movement and no flexibility when the ski bends.

In practice, this design has not proven successful, because with flexingmovements of the ski, considerable stresses can occur between thehousing and the toothed racks, so that after prolonged use, the correctengagement of gearwheel and toothed racks cannot be guaranteed with thedesired certainty.

SUMMARY OF THE INVENTION

Essentially a basic arrangement of the type defined in the preamble,however, offers the advantageous possibility of adapting a bindingquickly to different ski boot sizes. Ski bindings with such basic partsare therefore especially suitable for use as loaners.

The object of this invention is to guarantee a high operatingreliability with a basic arrangement of the type defined in the preamblewith a simple construction.

This object is achieved according to this invention by the fact that thegearwheel has a locked position rigidly mounted on the ski and thetoothed racks are mounted so they can pivot about a transverse axis inthe meshing zone of the gearwheel.

This invention is based on the general idea of preselecting a fixedposition for the locked gearwheel relative to the neighboring zone ofthe. ski and designing the meshing of the gearwheel and toothed rack sothat the toothed racks remain tiltable about a transverse axis of theski in the meshing zone and accordingly can largely freely followflexing movements of the ski in which the front and rear end of the skiare bent upward relative to the middle of the ski.

The meshing zone can be predefined accurately by a ski-side support ofthe toothed racks at the aforementioned pivot axis.

According to a preferred embodiment of this invention, the gearwheel isarranged on another base part which is separate from the front and rearbase parts and is essentially stationary on the ski and can beindirectly over the front and rear base parts in a stationary mount onthe ski in an especially preferred manner. According to this embodiment,the base parts for guiding the carrying parts and for bearing of thegearwheel are designed in the manner of a flexible linked belt, whichcan follow the flexing movements of the ski easily.

In addition, in an expedient embodiment of this invention, the gearwheelmay be arranged to be axially movable against a spring force such thatthe spring force of the gearwheel applies tension in the lockedposition.

Very strong springs may be provided here, so that the gearwheel can belifted out of its locked position only by means of a separately operatedunlocking element.

In the unlocked position of the gearwheel, the unlocking element or itshandle assumes an obtrusive position which interferes in skiing, so thatthe fact that it is unlocked will be noticed in any case.

The position of the unlocking element allocated to the locked positionof the gearwheel is preferably designed as a catch position, where thespring system putting tension on the gearwheel into its locked positionmay also act as a catch spring system.

According to an especially preferred embodiment, the gearwheel can beadjusted by means of a lever into the locked position and the unlockedposition, whereby in the unlocked position of the gearwheel, the leverprojects beyond the longitudinal edge of the ski and is put undertension into its position locking the gearwheel by a spring system. Theposition of the lever unlocking the gearwheel is expediently designed astop dead center.

DESCRIPTION OF THE DRAWING

Moreover, with regard to preferred features of this invention, referenceis made to the claims and the following explanation of the drawing onthe basis of which some especially preferred embodiments of thisinvention are explained in greater detail.

They show:

FIG. 1 a top view of a ski binding with a base arrangement according tothis invention;

FIG. 2 a schematic side view of the binding mentioned above;

FIG. 3 a sectional view according to sectional line IIIIII in FIGS. 1and 2;

FIG. 4 a perspective view of an adjustment handle for adjusting thesupporting parts;

FIG. 5 a single diagram of an unlocking element;

FIG. 6 a single diagram of a lifting ring that works together with theunlocking element;

FIG. 7 a perspective view of a modified base arrangement as seen frombeneath;

FIG. 8 the respective gearwheel;

FIG. 9 the respective link ring, and

FIG. 10 the respective control lever.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

According to FIGS. 1 and 2, flat base parts 2 through 4 are arranged ona ski 1, with only the front and rear base parts 2, 4 being bolteddirectly to the ski 1 (screws not shown), while the middle base part 3is secured in a stationary mount on the ski indirectly through the twoother base parts 2 and 4. Through a suitable dimensioned gap between thebase parts 2 and 4, it is possible to guarantee that the base parts 2and 4 form a link belt, which freely follows the flexing movements ofthe ski 1.

Guide rails, e.g., those with a C profile, are arranged on the laterallongitudinal edges of the front and rear base parts 2 and 4, with theconcave sides of the rail profiles facing one another. A frontsupporting part 6 for a ski boot holding part or toe binding 7 on thetoe end and a rear supporting part 8 for a ski boot holding part or heelbinding 9 on the heel end are displaceably guided, with a ski brake 10which is connected to the rear supporting 8 or the heel binding 9 beingassigned to this part.

Each supporting part 6 and 8 is fixedly connected to a toothed rack 11and 12, with the teeth on these two toothed racks 11 and 12 being meshedwith the gearwheel 13 on a manually operable hand wheel 14, which isrotationally mounted on an axle 15 which is arranged in a fixed mount ona base part 3 and is visible only in FIG. 3; it is adjustable axially ina manner to be explained below between a locked position in which handwheel 14 cannot be rotated with the gearwheel and an adjustment positionin which the hand wheel can be rotated with the gearwheel with asimultaneous adjustment of the supporting parts 6 and 8 as well as theski boot holding parts 7 and 9.

According to FIG. 3, the axle 15 integrally molded on the base part 3has a central inside thread borehole and axial grooves 16 on its outercircumference.

The axle 15 passes through the bearing eye 17 of an unlocking lever 18which is shown in a perspective view in FIG. 5 and can be pivoted out ofits normal position, shown with solid lines in FIG. 3, into its unlockedposition, shown with dotted lines, the purpose of which is to beexplained in greater detail below. Three cams 19 whose cam faces havethe shape of semicircular arcs are arranged centrally with the bearingeye 17 on the side of the unlocking lever 18 facing away from the basepart 3.

In addition, the axle 15 passes through the lifting ring 20 which isshown in a perspective view in FIG. 6, axial webs 21 being integrallymolded on its inside circumference in the axial grooves 16 of the axle,securing the lifting ring 20 so it cannot rotate relative to the axle15, but permitting axial displacement of the lifting ring 20. Thelifting ring 20 has link-type recesses 22 which are open toward itslower side and its outer circumference and work together with the cams19 of the unlocking lever 18. In the normal position of the unlockinglever 18, the cams 19 are accommodated by recesses 22. When theunlocking lever 18 is pivoted into the unlocked position, the cams slideover the ramp-shaped flanks 22′ of the recesses 22, so that the liftingring 20 is necessarily adjusted from its lower normal position,illustrated in FIG. 3, into its raised unlocked position, which isassigned to the unlocked position of the unlocking lever 18 as shownwith dotted lines in FIG. 3.

Finally, the axle 15 passes through a stepped central borehole 23 in thehand wheel 14. This central borehole 23 is designed so that its lowersection, which is enlarged in a step shape, is adapted to the outercircumference of the lifting ring 20, while the section of the centralborehole 23 having a smaller diameter is adapted to the outside diameterof the axle 15. Accordingly, the hand wheel 14 may assume its lowerposition illustrated in FIG. 3 only when the lifting ring 20 and theunlocking lever 18 assume their positions shown in FIG. 3.

As shown especially in FIG. 4, which shows a perspective view of thehand wheel 14 from beneath, the gearwheel 13 which is made of metal isinjected into the hand wheel 14 made of plastic in such a way thatanother gearwheel 24 made of plastic and having the same contours isformed on the lower side of the gearwheel 13. The gearwheels 13 and 24work together with the toothed racks 11 and 12 in a manner to beexplained below.

Moreover, a fine gearing 25 in comparison with the gearing on gearwheels13 and 24 is provided on the lower side of the hand wheel 14 in a radialplane above the gearwheel 13; its function will be explained in greaterdetail below.

A ring disk 27, whose outside circumference is enclosed by a ring webintegrally molded on the top of the hand wheel 14, is attached to theupper end of the axle 15 by means of a screw 26 screwed into the insidethread borehole of the axle 15.

Beneath the ring disk 27 there remains an annular space 28 axiallybetween the hand wheel 14 and the ring disk 27, surrounding the axle 15and accommodating a ring-shaped cup-spring assembly 29 or a helicalspring with a suitable diameter. This cup-spring assembly 29 or thehelical spring is clamped axially between the ring disk 27 and the handwheel 14 so that the hand wheel 14 is forced downward with aconsiderable force.

A housing part 30 is arranged fixedly relative to the base part 3axially between the hand wheel 14 and the base part 3, having channelsopen toward its lower side to accommodate the toothed racks 11 and 12. Agearing ring 31 is integrally molded on the top side-of the housing part30 and works together with the gearing 25 on the lower side of the handwheel 14.

Beneath the toothed racks 11 and 12 are arranged supporting bodies onthe housing part 30 or on the base part 3; these supporting bodiessupport the toothed racks 11 and 12 essentially only in the area ofsectional plane III—III in FIGS. 1 and 2. For example, the supportingbodies 32 may be designed in the form of a roof with the tip of the rooffalling in the sectional plane III—III.

The arrangement illustrated here functions as follows: Normally the handwheel 14 sits in the normal position shown in FIG. 3. This is equivalentto hand wheel 14 meshing with its gearing 25 in the gearing ring 31 ofthe housing part 30 and blocking it in a rotationally fixed manner. Inaddition, in this position of hand wheel 14, the metal gearwheel 13which is fixedly connected to it meshes with the gearing of the toothedracks 11 and 12, so that toothed racks 11 and 12 and the respectivesupporting parts 6 and 8 accordingly are also secured.

If the ski 1 executes flexing movements, i.e., if the ends of the skisare bent upward relative to the center of the ski, there is a certainsagging in the middle area of the ski, with the result that thesupporting parts 6 and 8 are shifted slightly in the longitudinaldirection of the ski on the base parts 2 and 4. In doing so, thedistance of the ski boot holding parts 7 and 9 may also change slightlyin the longitudinal direction of the ski. This does not matter forholding a ski boot (not shown) inserted into the ski boot holding parts7 and 9, because these changes in distance are compensated by the factthat one of the ski boot holding parts 7 and 9, usually the ski bootholding part 9 on the heel end, has limited mobility in the longitudinaldirection of the ski relative to the respective supporting part 6 or 8and is pushed in the direction of the other ski boot holding part,respectively, by a thrust spring system (not shown).

With the above-mentioned flexing movements of the ski 1, the toothedracks 11 and 12 execute more or less marked pivoting movements withregard to a transverse axis of the ski in the area of supporting bodies32. Due to the supporting bodies 32, it is reliably guaranteed that themeshing of the gearing on the toothed racks 11 and 12 in the gearing ofthe metal gearwheel 13 will be maintained.

Essentially, the ski 1 may also execute counter-flexing movements inwhich the ends of the ski are bent downward relative to the middle areaof the ski. However, the middle area of the ski is practically not bentat all, so that base parts 2 and 4 and thus the supporting parts 6 and 8carried in them and accordingly also the respective toothed racks 11 and12 do not execute any counter-flexing movements relative to one anotherand the meshing between the metal gearwheel 13 and the gearing of thetoothed racks 11 and 12 is reliably maintained.

If the unlocking lever 18 is pivoted from its normal position, shownwith solid lines in FIG. 3, into the unlocked position shown with dottedlines, the cams 19 raise the lifting ring 20 so that the hand wheel 14is also raised against the force of the spring system 29 and the gearing25 of the hand wheel 14 is released from the gearing ring 31 of thehousing part 20. The hand wheel 14 can thus be turned manually, so thatin this rotating position of the hand wheel 14, the plastic gearwheel 24adjacent to the metal gearwheel 13 cooperates with the toothed racks 11and 12. By rotating the hand wheel 14, the supporting parts 6 and 8 andthus the ski boot holding parts 7 and 9 can be adjusted simultaneouslyto adjust their spacing to different boot sizes in the longitudinaldirection of the ski. The length of the sole set in each case mayoptionally be read on a scale optionally provided on the hand wheel.14which can work together with a mark on the housing part 30.

As soon as the desired ski boot length has been set, the unlocking lever18 is reset from its unlocked position into the normal position, so thatthe cams 19 of the unlocking lever 18 can in turn assume a positionbeneath the recesses 22 on the lifting ring 20, and the spring assembly29 puts the hand wheel 14 together with its lifting ring 20 in its lowerend position. Thus the hand wheel 14 is again locked in a rotationallyfixed manner by meshing of its gearing 25 with the gearing ring 31 ofthe housing part 30. At the same time, the unlocking lever 18 is lockedin its normal position because the cams 19 are secured in the recesses22 of the lifting ring 20, which is non-rotating relative to the axle15, and thus the unlocking lever 18 is secured against rotation.

In deviation from the embodiment illustrated in the drawing, the gearing25 of the hand wheel 14 and the gearing ring 31 of the housing part 30which works together with it are omitted when, instead of that, thegearwheel 13 has a greater axial width and meshes with the gearing ofthe toothed racks 11 and 12 in the lower end position of the hand wheel14 on the one hand and with immovable gearing (not shown here) on thehousing part 30 beneath the lower side of toothed racks 11 and 12.

The advantage of the embodiment illustrated in the drawing is that thegearings 25 and 31 working together to lock the hand wheel 14 may bedesigned to be very fine, and the gearings of toothed racks 11 and 12and that of gearwheel 13 may be designed to be comparatively large, asis advantageous for the pivotability of toothed racks 11 and 12 relativeto a transverse axis in the meshing zone of the gearwheel 13 in toothedracks 11 and 12. The fine gearings 25 and 31 guarantee that the handwheel 14 can be locked in rotational positions very close together.

Moreover, in deviation from the embodiment illustrated in the drawing,the unlocking lever 18 and the lifting ring 20 may also be omitted, andhand wheel 14 combined with or connected to the gearwheel 13, 24 may begripped directly by hand to unlock it and lifted relative to ski 1 toperform a rotational adjustment.

In the embodiment in FIGS. 7 through 10, a pivot lever 40 which canrotate about the axle of the hand wheel 14 is provided, with which thehand wheel 14 together with its gearwheels 13 and 24 can be raised intoits unlocked position relative to the ski as well as being lowered intoits locked position. The arrangement is designed so that the handle ofthe pivot lever 40 projects laterally far beyond the longitudinal edgeof the ski when the pivot lever is adjusted out of the positionillustrated in FIG. 7, where the hand wheel 14 is locked, into theposition in which the hand wheel 14 is unlocked.

According to FIG. 7, the pivot lever 40 is connected to a guide rod 41in an articulated connection which is displaceable guided between twostationary abutments 42. Between these abutments 42 and the end of theguide rod 41 on the pivot lever end, a helical spring 43 concentric withthe guide rod 41 is clamped, applying tension to the pivot lever 40 inthe position shown in FIG. 7, or it can be held in its other pivoted endposition which is designed as top dead center.

According to FIG. 10, screw hooks 44 are punched on the pivot lever 40,engaging in helical grooves 45 of a link ring 46, shown in greaterdetail in FIG. 9, and held within the base part 3 so it is axiallymovable but non-rotatable.

This link ring 46 has an inner peripheral groove 47 meshing with theradial projections 48 arranged on the hand wheel 14 according to FIG. 8.To permit assembly of the link ring 46 on the hand wheel 14, the linkring 46 may be designed as a C-shaped spring ring which can be spreadapart elastically to allow the radial projections 48 to be snapped intothe inner peripheral groove 47.

When pivot lever 40 is pivoted about its pivot axis, the screw hooks 44are displaced into the helical grooves 45 in the link ring 46 which isheld non-rotatably, so that it executes an axial lifting movement inwhich the hand wheel 14 engaging with the radial projections 48 in theinner peripheral groove 47 of the link ring 46 is necessarily entrained.Thus, the hand wheel 14 can be adjusted in its locked position, loweredonto the ski, on the one hand and into its unlocked position which israised relative to the ski on the other hand and in which the liftingring 20 can be rotated by displacement of the toothed racks 11 and 12(see FIG. 1).

Through the basic arrangement according to this invention, a veryadvantageous pressure distribution is achieved between ski 1 and thesubstrate in skiing.

Since the front and rear base parts 2 and 4 which are screwed to the ski1 reach around the middle base part 3 on its top side from above, theweight of the skier, which is applied to the ski boot holding parts 7and 9 on the front and rear base parts 2 and 4, or the load exerted bythe skier on the ski is also transmitted to the ski to a great extentover the middle base part 3. This effect is especially pronounced whenthe ski 1 sags, i.e., when the ends of the ski 1 are bent upwardrelative to the center zone of the ski 1, as is the case when cornering,for example, with a marked use of the edges of the ski on the runningsurface of the ski 1, especially in the so-called carving technique. Insuch bending movements of the ski 1, the middle base part 3 attempts toapproach the top side of the ski vertically from overreaching parts ofthe base parts 2 and 4 from above, with the result that the middle basepart 3 is pressed to a greater extent against the top side of the skiand the bottom pressure of the middle zone of the ski or the ski edgeengaging at the bottom is greatly increased in the area of the middlezone, so the bottom pressure reaches a maximum in the area of the middlezone of the running surface or the edge of the ski 1 used, and itdecreases continuously in both forward and reverse directions in thelongitudinal direction of the ski.

Therefore, the three-part design of the basic arrangement shown here isalso advantageous if an arrangement for simultaneous adjustment of theski boot holding parts 7 and 9 for adjusting to the respective ski bootlength is omitted. With such an arrangement, the ski boot holding parts7 and 9 are arranged in an essentially fixed manner according to apredefined ski boot size on the front and rear base parts 2 and 4, witha ski boot holding part, usually the ski boot holding part 9 on the heelend, is displaceable in the longitudinal direction of the ski againstthe above-mentioned thrust spring system, to the rear in the case of theski boot holding part 9 on the heel end to prevent unwanted tensionbetween the ski 1 and the rigid sole of the ski boot when there arebending movements of the ski 1. The middle base part forms a “fillerpart” between the other base parts 2 and 4, this part in turn beingpressed against the top side of the ski from the iddle base part 3 bythe overreaching parts of the other base parts 2 and 4 or being pressedwith increased force against the top side of the ski when there issagging of the ski 1.

In all embodiments, the middle base part 3 can thus be held verticallyrigidly on the ski 1 by the parts of the other base parts 2 and 4reaching over this base part 3 from above.

For holding in the longitudinal and transverse directions of the ski,the middle base part 3 may be connected to one of the other base parts 2and 4, e.g., base part 4, in such a way that it is flexible or can bepivoted about a transverse axis of the ski, e.g., by a flexible sole inthe form of a flat strip on the bottom side of the two base parts 3 and4 connected together. In this arrangement, the middle base part 3 shouldbe arranged so it is displaceable in the longitudinal direction of theski relative to the top side of the ski and the base part 2 which isseparate from base part 3.

Essentially, the middle base part 3 may also be secured on the ski 1.Again in this case, the above-mentioned pressure distribution betweenthe ski 1 and the substrate in skiing is also achieved if the base parts2 and 4 arranged in a fixed position on the ski extend over the middlebase part 3 on its front and rear end areas and press against the topside of the ski, especially with bending movements of the ski 1.

In all these embodiments, the parts of the other base parts 2 and 4reaching over the top side of the middle base part 3 from above shouldslide well on the base part 3. In addition, transverse joints should bearranged at both ends of the base part 3 between the adjacent base parts2 and 3 as well as 3 and 4 beneath the parts of the base parts 2 and 4which extend over the base part 3 from above. These measures guarantee agood flexibility of the ski 1.

A pressure distribution that is at least partially improved is alsoachieved when only one of the base parts 2 and 4 extend over the middlebase part 3 from above.

The invention has been described with particular emphasis on thepreferred embodiments, but variations and modifications within thespirit and scope of the invention may occur to those skilled in the artto which the invention pertains.

What is claimed is:
 1. A basic arrangement of a ski binding having afront boot holding part or a toe end for securing a ski boot, a firstbase part fixed on the ski, a front supporting part longitudinallydisplaceable on the first base part, said front supporting partsupporting the front boot holding part, a rear boot holding part or aheel end for securing the ski boot, a second base part fixed on the ski,a rear supporting part longitudinally displaceable on the second basepart, said rear supporting part supporting the rear boot holding part, arack-and-pinion gear adjusting device for simultaneous adjustment ofboth said front supporting part and said rear supporting part, saiddevice having two toothed racks, the first rack connected to the frontsupporting part and the second rack connected to the rear supportingpart, and a manually operable, lockable gearwheel which meshes with bothtoothed racks between the two supporting parts, wherein the gearwheelhas a locked position in a fixed position on the ski, and the toothedracks are arranged pivotally about a transverse axis of the ski in themeshing zone of the gearwheel, and the gearwheel has an unlockedposition which is raised vertically relative to the top side of the skifor the rotational adjustment and a locked position which is depressedtoward the top side of the ski.
 2. A basic arrangement according toclaim 1, wherein a spring system holds the gearwheel under tension inthe locked position.
 3. A basic arrangement according to claim 1,wherein the gearwheel adjoins a plastic hand wheel and a secondgearwheel which has the same contour as the gearwheel and when saidgearwheel is in the locked position, said second gearwheel workstogether with the toothed racks and when said gearwheel is in theunlocked position, said gearwheel works together with the toothed racks.4. A basic arrangement according to claim 2, wherein the gearwheel andthe second gearwheel have a lower position or a catch position securedby the spring system and are lifted by a lifting device against theforce of the spring system.
 5. A basic arrangement according to claim 1,wherein a lever lifts the gearwheel out of the locked position andadjust into the locked position, with the lever projecting over alongitudinal edge of the ski when the gearwheel is unlocked.
 6. A basicarrangement according to claim 5, wherein a spring arrangement undertension puts the lever into the position locking the gearwheel, and theposition of the lever unlocking the gearwheel is top dead center.
 7. Abasic arrangement according to claim 3, wherein said gearwheel is metal.8. A basic arrangement according to claim 3, wherein said secondgearwheel is plastic.
 9. A basic arrangement of a ski binding having; afront boot holding part or a toe end for securing a ski boot; a firstbase part fixed on the ski; a front supporting part longitudinallydisplaceable on the first base part, said front supporting partsupporting the front boot holding part; a rear boot holdings part or aheel end for securing the ski boot; a second base part fixed on the ski;a rear supporting part longitudinally displaceable on the second basepart, said rear supporting part supporting the rear boot holding part; arack-and-pinion gear adjusting device for simultaneous adjustment ofboth said front supporting part and said rear supporting part, saiddevice having two toothed racks, the first rack connected to the frontsupporting part and the second rack connected to the rear supportingpart, and a manually operable, lockable gearwheel which meshes with bothtoothed racks between the two supporting parts; a third base part in anessentially stationary mount on the ski, said third base part beingseparate from the first and second base parts and said third base partbeing held indirectly on the ski by the first and second base parts torestrict movement of said third base part, wherein the gearwheel isarranged on the third base part, and the gearwheel has a locked positionin a fixed position on the ski, and the toothed racks are arrangedpivotally about a transverse axis of the ski in the meshing zone of thegearwheel, wherein the gearwheel is fixedly arranged or integrallymolded on a hand wheel, and the hand wheel and the gearwheel have avertically raised position with respect to the top side of the ski forthe rotational adjustment, a locked position depressed toward the topside of the ski, and a meshing position wherein at least one of thegearwheel or a gearing provided on the hand wheel meshes with astationary lock gearing and works together with the lock gearing.